resolved: properly check return value of dns_resource_record_equal()

src/resolve/resolved-dns-cache.c

@@ -224,7 +224,7 @@ static DnsCacheItem* dns_cache_get(DnsCache *c, DnsResourceRecord *rr) {
         assert(rr);
 
         LIST_FOREACH(by_key, i, hashmap_get(c->by_key, rr->key))
-                if (i->rr && dns_resource_record_equal(i->rr, rr))
+                if (i->rr && dns_resource_record_equal(i->rr, rr) > 0)
                         return i;
 
         return NULL;

src/resolve/resolved-dns-packet.c

@@ -1029,6 +1029,8 @@ static bool loc_size_ok(uint8_t size) {
 }
 
 static int dnskey_parse_flags(DnsResourceRecord *rr, uint16_t flags) {
+        assert(rr);
+
         if (flags & ~(DNSKEY_FLAG_SEP | DNSKEY_FLAG_ZONE_KEY))
                 return -EBADMSG;
 

src/resolve/resolved-dns-zone.c

@@ -104,7 +104,7 @@ static DnsZoneItem* dns_zone_get(DnsZone *z, DnsResourceRecord *rr) {
         assert(rr);
 
         LIST_FOREACH(by_key, i, hashmap_get(z->by_key, rr->key))
-                if (dns_resource_record_equal(i->rr, rr))
+                if (dns_resource_record_equal(i->rr, rr) > 0)
                         return i;
 
         return NULL;